One proposed structure of a vehicle includes an engine, a planetary gear of which a career is connected to an output shaft of the engine, a generator connected to a sun gear of the planetary gear, and a motor connected via a transmission to a ring gear of the planetary gear (see, for example, Patent Document 1). In this proposed vehicle, the output torque of the motor is maintained until the rotation speed of the motor is close to the rotation speed after changing gear in the transmission and then the output torque of the motor is smoothly changed into the torque after changing gear in the transmission when the gear change in the transmission is executed outputting the torque from the motor to an axel. This technique ensures the reduction of the torque shock caused when the gear ratio of the transmission is changed.
Patent Document 1: Japanese Patent Laid-Open No. 2006-56343